Evolution of the Liquid Biopsy in Metastatic Prostate Cancer.

We reviewed the literature for the biologic, prognostic, and predictive significance of circulating prostate cancer tumor cells (CTCs), and circulating tumor DNA in the blood of metastatic castration resistant prostate cancer patients. CTCs demonstrate robust prognostic value independent of PSA in predicting overall survival. The CTC androgen receptor variant receptor 7 phenotype predicts resistance to androgen receptor synthesis inhibitors and sensitivity to taxane based chemotherapy in metastatic castration resistant prostate cancer patients who are candidates for second line therapy. Research is rapidly pivoting toward circulating tumor DNA analysis because the approach is sensitive, prognostic, cost effective, and it can elucidate mechanisms of systemic therapy.

Global gene expression profiling of circulating tumor cells.

Metastases from primary tumors are responsible for most cancer deaths. It has been shown that circulating tumor cells (CTCs) can be detected in the peripheral blood of patients with a variety of metastatic cancers and that the presence of these cells is associated with poor clinical outcomes. Characterization of CTCs in metastatic cancer patients could provide additional information to augment management of the disease. Here, we describe a novel approach for the identification of molecular markers to detect and characterize CTCs in peripheral blood. Using an integrated platform to immunomagnetically isolate and immunofluorescently detect CTCs, we obtained blood containing > or = 100 CTCs from one metastatic colorectal, one metastatic prostate, and one metastatic breast cancer patient. Using the RNA extracted from the CTC-enriched portion of the sample and comparing it with the RNA extracted from the corresponding CTC-depleted portion, for the first time, global gene expression profiles from CTCs were generated and a list of cancer-specific, CTC-specific genes was obtained. Subsequently, samples immunomagnetically enriched for CTCs from 74 metastatic cancer patients and 50 normal donors were used to confirm by quantitative real-time reverse transcription-PCR CTC-specific expression of selected genes and to show that gene expression profiles for CTCs may be used to distinguish normal donors from advanced cancer patients as well as to differentiate among the three different metastatic cancers. Genes such as AGR2, S100A14, S100A16, FABP1, and others were found useful for detection of CTCs in peripheral blood of advanced cancer patients.

Caracterización fisicoquímica y microbiológica de aguas subterráneas de un sector rural a baja altitud en Los Andes venezolanos / Physicochemical and microbiological characterization of groundwater wells of a rural sector located at low altitude in the venezuelan Andes

El crecimiento de la población humana y las actividades antropogénicas ha aumentado la tasa de contaminación del agua subterránea en el mundo, por lo que, la finalidad de este estudio es determinar la potabilidad del agua de cuatro pozos subterráneos de un área rural del estado Mérida, mediante la caracterización fisicoquímica y microbiológica, para comprobar la factibilidad de su uso como agua de consumo. Los resultados indican que los parámetros fisicoquímicos cumplen la normativa venezolana. Las aguas presentan una gran variedad de minerales destacándose Ca, Na y Mg como cationes mayoritarios y una dureza básicamente debía a iones bicarbonato. Los valores de la distribución isotópica, sugieren la existencia de dos acuíferos sin conexiones hidráulicas entre los pozos. El análisis bacteriológico y parasitológico detecta: bacterias heterótrofas, coliformes totales y Pseudomonas, así como, Ascaris spp., Blastocystis sp., Giardia sp., y Eimeria sp., probablemente procedentes del filtrado subterráneo de los pozos sépticos y percolado desde la superficie a través del suelo de textura franco arcilloso arenoso, microorganismos que se han adaptado a las características fisicoquímicas de las aguas. Los resultados demuestran que el agua de tres pozos, no puede ser utilizada para el consumo, sin previo tratamiento convencional como coagulación, filtración y cloración

Growth in human population and anthropogenic activities has increased the rate of groundwater pollution in the world, therefore, the purpose of this study is to determine the potability of water from four underground wells in a rural area of Mérida State, through the physicochemical and microbiological characterization, to check the feasibility of its use as drinking water. The results indicate that the physicochemical parameters comply with venezuelan regulations. The waters have a wide variety of minerals, highlighting Ca, Na and Mg as majority cations and a hardness basically due to bicarbonate ions. The values of the isotopic distribution suggest the existence of two aquifers without hydraulic connections between wells. Bacteriological and parasitological analysis detects: heterotrophic bacteria, total coliforms and Pseudomonas, as well as Ascaris spp., Blastocystis sp., Giardia sp., and Eimeria sp., probably derived from the underground filtration of septic tanks and percolated from the surface through the sandy clay loam soil, microorganisms that have adapted to the physicochemical characteristics of waters. The results show that the water from three wells cannot be used for consumption without some conventional treatment as filtration and coagulation, and disinfection process

Dispersión hídrica de enteroparásitos en una zona agropecuaria de gran altitud, en Los Andes Ecuatorianos / Water dispersion of enteroparasites in a high-altitude agricultural area, in The Ecuadorian Andes

La finalidad de esta investigación fue determinar las especies de enteroparásitos que son vehiculizadas por agua de regadío, entubada y estancada, como factor de riesgo asociado a la transmisión en una comunidad rural de la provincia de Chimborazo-Ecuador. Se realizó una investigación de campo, transversal, con muestreo no probabilístico intencional, en el que se incluyeron 214 muestras de agua: 37 de canales de riego, 147 que surten las viviendas y 30 estancadas. Las muestras se analizaron mediante Sedimentación espontánea, técnica de Bailenger (modificada) y coloración de Ziehl Neelsen (modificada). El agua de regadío y la estancada, obtuvieron el 100% de contaminación parasitaria y en menor grado la entubada, con 57,14%. La mayor proporción fue de protozoarios (70,56%), seguidos de chromistas (40,65%) y helmintos (13,08%). Entre los parásitos transmisibles, se destacan: Blastocystis spp. (40,65%), Amebas de vida libre (5,61%), Entamoeba spp. (8,41%), Giardia duodenalis (6,54%), Balantidium spp. (13,51%), Cryptosporidium spp. (17,76%), Cyclospora spp. (3,74%), Cystoisospora spp. (2,34%), Eimeria spp. (13,55%), Dibothriocephalus spp. (0,47%) y larvas de nemátodos (13,08%). Los resultados evidencian la presencia de parásitos de transmisión hídrica en los tres cuerpos de agua estudiados, lo que constituye un riesgo de infección humana, veterinaria y de contaminación para los productos agrícolas

The purpose of this investigation was to determine the species of enteroparasites that are carried by irrigated, piped and stagnant water, as a risk factor associated with transmission in a rural community in the province of Chimborazo-Ecuador. A cross-sectional field investigation was carried out, with an intentional non-probability sampling, in which 214 water samples were included: 37 from irrigation canals, 147 that supply the houses and 30 stagnant. The samples were analyzed by spontaneous sedimentation, Bailenger technique (modified) and Ziehl Neelsen staining (modified). Irrigation and stagnant water obtained 100% of parasitic contamination and to a lesser extent piped, with 57.14%. The highest proportion was of protozoa (70.56%), followed by chromists (40.65%) and helminths (13.08%). Among the transmissible parasites, the following stand out: Blastocystis spp. (40.65%), Free-living amoebas (5.61%), Entamoeba spp. (8.41%), Giardia duodenalis (6.54%), Balantidium spp. (13.51%), Cryptosporidium spp. (17.76%), Cyclospora spp. (3.74%), Cystoisospora spp. (2.34%), Eimeria spp. (13.55%), Dibothriocephalus spp. (0.47%) and nematode larvae (13.08%). The results show the presence of parasites of water transmission in the three bodies of water studied, which constitutes a risk of human, veterinary infection and contamination for agricultural products

Novel use of the gelport to expedite transition to robot-assisted partial nephrectomy.

Robot-assisted partial nephrectomy is associated with a learning curve, necessitating proficiency in robotic renal dissection, hilar control, and subsequent mass excision and renorrhaphy. The Gelport can be used during these procedures to expedite initial control of the renal pedicle and to add to the surgeon's comfort level while transitioning to this procedure.

Circulating tumor cells predict survival in patients with metastatic prostate cancer.

OBJECTIVES: To determine whether circulating tumor cells (CTCs) predict for survival in patients with metastatic prostate cancer (PCa) and to compare its prognostic abilities with other clinical factors. METHODS: Blood samples from 37 patients with metastatic PCa were analyzed for CTCs. CTCs were enriched from 7.5 mL blood using magnetic nanoparticles targeting the epithelial cell adhesion molecule and then fluorescently labeled. The samples were analyzed by multiparameter flow cytometry, and events with appropriate light scatter properties that were nucleic acid dye positive, cytokeratin positive, and CD45 negative were defined as CTCs. RESULTS: The number of CTCs found ranged from 0 to 8586 per 7.5 mL (mean 530 +/- 1887, median 5). A threshold of 5 or more CTCs per 7.5 mL of blood was used to evaluate the ability of CTCs to predict for overall survival. Of the 37 patients, 23 (62%) had 5 or more CTCs, with a median overall survival of 0.70 year compared with more than 4 years for those patients with fewer than 5 CTCs (log-rank P = 0.002, Cox hazards ratio 7.4). In the subset of 26 patients with hormone-refractory PCa, the presence of CTCs was the most significant parameter predictive of survival in univariate and multivariate analyses. CONCLUSIONS: In this pilot study, the presence of 5 or more CTCs in 7.5 mL blood was associated with poor overall survival in patients with metastatic PCa.

Multigene reverse transcription-PCR profiling of circulating tumor cells in hormone-refractory prostate cancer.

BACKGROUND: Circulating tumor cells (CTCs) represent a surrogate source of tissue and conceptually represent a "real-time" biopsy. We previously reported that the number of CTCs mirrors disease progression in hormone-refractory prostate cancer (HRPC). To improve characterization of CTCs we further investigated whether in vitro transcription-based multigene reverse transcription-PCR expression profiles could be obtained from CTCs in HRPC. METHODS: We evaluated the expression of 37 genes with potential utility for epithelial cell characterization from antisense RNA libraries constructed from immunomagnetically enriched CTCs from 7.5-mL blood samples from healthy donors and patients with HRPC. RESULTS: In the control group 13 of 37 genes were not expressed. The most notable of the genes expressed in CTCs of 23 blood specimens drawn from 9 patients with metastatic prostate cancer were prostate-specific antigen (20 of 23; 87%), prostate-specific membrane antigen (17 of 23; 74%), androgen receptor (16 of 23; 70%), human glandular kallikrein 2 (7 of 23; 30%), epidermal growth factor receptor (4 of 23; 17%), and prostate-specific gene with homology to G protein receptor (2 of 23; 9%). The number of CTCs in these samples ranged from 4 to 283 in 7.5 mL of blood (mean, 87; median, 89). Expression of some of the genes was low in the control samples and higher in the patient samples. In all 23 samples, cytokeratin 19, epithelial cell adhesion molecule, or mucin 1 was expressed. Because of background expression in the controls, expression of 13 of the 37 genes, including HER-2, p53, and BCL-2, could not be measured in CTCs. CONCLUSION: Antisense RNA libraries can be constructed from CTCs and gene expression profiles of CTCs obtained from patients with HRPC. This could enhance the characterization of HRPC and facilitate the development of more effective therapies.

Apoptosis of circulating tumor cells in prostate cancer patients.

BACKGROUND: The prescence of circulating tumor cells (CTCs) in the peripheral blood of cancer patients and their frequency has been correlated with disease status. METHODS: In this study, CTCs were characterized by flow cytometry and fluorescence microscopy after immunomagnetic enrichment from 7.5-ml blood samples collected from patients with prostate cancer in evacuated blood-draw tubes that contained an anticoagulant and a preservative. Events were classified as tumor cell candidates if they expressed cytokeratin, lacked CD45, and stained with the nucleic acid dye 4,6-diamidino-2-phenylindole. RESULTS: In the blood of prostate cancer patients, only few of these events were intact cells. Other CTC events appeared as damaged cells or cell fragments by microscopy. By flow cytometry, these events stained variably with 4,6-diamidino-2-phenylindole and frequently expressed the apoptosis-induced, caspase-cleaved cytokeratin 18. Similar patterns of cell disintegration were observed when cells of the prostate line LNCaP were exposed to paclitaxel before spiking the cells into normal blood samples. CONCLUSIONS: The different observed stages of tumor cell degradation or apoptosis varied greatly between patients and were not found in blood of normal donors. Enumeration of CTCs and identification of CTCs undergoing apoptosis may provide relevant information to evaluate the response to therapy in cancer patients.